Pretty Little Liars fans finally discovered who A was last night - and they're really not happy.

CeCe Drake was revealed as the texting terror formerly known as Charles DiLaurentis after Spencer, Hanna, Aria, Emily and Mona tracked down their torturer after she kidnapped her own sister Alison.

Fans have reacted with fury after CeCe - played by actress Vanessa Ray - was exposed because before tonight's episode she had been known as Jason's girlfriend meaning the show has entered the realms of incest.

CeCe is A and was Charles, Charlotte and Charlie and dating her own brother (Image: ABC)

But more than that fans are angry that the ABC Family drama seemingly linked CeCe's being transgender with her psychopathic tendancies.

Over six years A has terrorised the girls and most recently kept the girls imprisoned in her 'dolls house' for three weeks where they were tortured, deprived of food and water and psychologically warped.

The show claimed CeCe was sent away to psychiatric institution Radley because of her transphobic father but then somehow escaped and became a multi-millionaire genius who funded a six-year campaign to destroy the lives of four teenage girls.

Safe to say the girls were shocked by this development (Image: ABC)

"That was by far the WORST storyline in history for PLL!" wrote one viewer. "Just a disappointment for true PLL fans. Ridiculous."

"I'm disappointed," added another. "I was expecting a huge, shocker-twist-surprise for the 'big' A reveal and it's been CeCe all along. Ridiculous. #PLL."

Cece's obsession with dolls proved troubling for fans (Image: ABC)

"Marlene King, your attempt at introducing a transgender character was horrific and quite offensive."